Hot water storage tank



y' 1959 o. P. BRAUN 2,893,589

HOT WATER STORAGE TANK Filed Oct. 16, 1953 0770 BRAUN United States Patent HOT WATER STORAGE TANK Otto P. Braun, Stuttgart, Germany Application October 16, 1953, Serial No. 386,625

3 Claims. (Cl. 220-) 7 The invention relates to an electrically heated warmv or hot water storage apparatus.

Warm or hot water storage tanks consisted heretofore of a storage vessel having a single wall of easing which latter was provided with a heat insulating layer surrounded by a suitable outer casing. For the material of the storage vessel one utilized a zinc coated copper sheet metal. Only at times of copper scarcity was it necessary to make water storage tanks of copper plated tanks or inner enameled sheet steel, porcelain and glass. Sheet steel even if carefully surface treated is not corrosion resistant while glass and porcelain lined containers present problems in passing the various tubes, pipes, tem perature regulators etc. through the walls thereof. Also ceramic storage tanks are not pressure resistant and can therefore only be used for overflow reservoirs.

It is therefore an object of the present invention to provide a storage tank with hot water resistant artificial materials pressed to form to be used as the walls of the tank which can withstand the inner and outer pressures. A further object according to the invention, resides essentially therein that the container wall or casing is composed of a plurality of column-like hollow rings arranged one over the other and interfitting so that each ring member will comprise an inner wall portion and an outer wall portion as inner and outer rings. Another object of the invention resides in the provision of rods or tension anchors to maintain the rings together. A still further object of the invention is to form the hollow rings as U-shaped' elements but of course they may comprise other shapes such as Z-shaped or H-shaped in cross section. It is of advantage to make the rings of such shape that the superposed hollow rings will form an air space which acts as an insulating medium.

It is also an object of the invention to provide the bottom and the top cover of the tank of two shell-like parts of double wall construction interconnected by reinforcing ribs.

Further objects will be apparent from the following description, when considered in connection with the accompanying drawing in which;

Figure 1 is a vertical section partly in side elevation of the storage tank,

Figure 2 is a partial section on an enlarged scale showing the wall construction of the upper part of the tank,

Figure 3 is a view similar to Figure 2 showing the lower part of the tank,

Figure 4 is a side elevation partly in section of the hollow rings showing a modified construction,

Figure 5 is a plan view of the radial rib construction of the inner shell of the cover, and

Figure 6 is a bottom plan view of the radial rib construction of the inner shell of the bottom member.

The cylindrical double-walled tank is composed of a plurality of hollow rings which are superposed one on the other. Each hollow ring member is composed of an inner ring section 1 and an outer ring section 2, both interconnected by a horizontal web section 3. As shown in Figures 1 and 2, these ring sections 1 and 2 with the horizontal section 3 form a U-shaped member and in Figure 4 an H-shaped member. In order to prevent a lateral movement or sliding of the hollow rings, each of the latter is provided with an annular step portion or shoulder 4 on each side as best seen in Figures 2 and 3 so that the adjacent rings fit on and into each other. In this way the sections 1 and 2 of each ring fit and rest on the shoulders 4 of the lower ring member so that by this interengaging means there is no possibility of any shifting of the rings relative to each other and also the rings will form a tight fit to prevent leakage of water through the ring sections 1 at the meeting edges. The joined and united series of rings can be suitably cemented or Welded to each other. It is preferable to use a plurality of tension rods to hold the rings together as shown by means of the rod 5 in Figure 4.

The cover of the storage tank, Figures 1, 2 and 5 is composed of two concentric shells or casings, namely the inner casing 6 and the outer casing 7, which are interconnected with each other by means of connecting flanges as radial ribs 8. These stays or cross pieces 8 are preferably integral with a central collar 9 as best shown in Figures 1 and 5. In the same manner as shown in Figures 1, 3 and 6 the bottom portion of the tank is provided as an inner casing or shell 10 and an outer casing or shell 11 interconnected by means of the radial ribs or stays 12 preferably integral with a central collar 13 as best shown in Figures 3 and 6. Also a flanged ring 14, Figures 1 and 3 may be provided integral with the ring 13 and this ring 14 is for the purpose of securing thereto the usual heating plates 15 which as shown in Figure 1 carry the electric heating element 22 as well as the control device 23 of a temperature regulator. As shown, the elements 22 and 23 extend from the plate 15 into the water space of the tank. The rings 13 and 14 may be made integral or they can be made separately and secured together by any suitable means such as by welding, etc.

The inner shells 6 and 10 of the cover and bottom are also provided with concentric rim member 16 and 17 to support the end inner rings 1 as shown in Figures 2 and 3 and which project over a portion of the inner surface of the end rings 1. Also the outer shells 7 and 11 are similarly provided with rim members 18 and 19 to receive a portion of the outer rings 2 of the two end rings. Also the outer rim members 18 and 19 may act to hold and receive an outer sheath or cover 20, Figures 1 to 3, if it is desired to provide a cover for the rings to present a more pleasing appearance for the tank. When the top and bottom members are produced by the pressure method it is advisable to provide the ribs 8 and 12 only with one casing as for example an inner casing all made of one piece, that is each top and bottom cover is integral with its ribs or stays. One may also provide an alternate construction of the stays and the top and bottom closures in that some of the stays 8 and 12 may be connected to the inner casings 6 and 19 respectively and the remaining stays may be connected to the outer. casings 7 and 11 respectively. The ring member 14 can also be made to receive a cover member 21 in order to protect the electrical and control members as shown in Figure 1. Also a suitable inlet pipe 24 and an outlet pipe 25 may pass through the bottom of the tank and these pipes permit the entry of cold water and the exit of hot water respectively. As usual the inlet pipe 24, by means of which cold Water is supplied, terminates close to the bottom of the tank While the outlet pipe 25 through which hot water is withdrawn, terminates near the top of the tank. The interconnected hollow rings may be suitably cemented to each other or welded as well 3 as secured together by means of screws or bolts. In order to secure water tight joints as to the inner rings 1 and the inner casings 6 and 10 forming the water space,

it ispossible to provide a tight layer of material to form.

a; complete inner coating. This can be accomplished in that the inner surface of the tank may becoated with a material in a plastic condition and applied by pressure or by other means. p

Due to the double walled structure practically sur rounding the entire tank, it is thus possible to provide a storage tank in which the air spaces between the inner and outer walls or casings form insulation layers. It is of course possible, if desired, to fill such air spaces be tween theinner and outer walls with an insulating ma terial such as glass wool, various fibers, etc.

It is ofcoui se obvious that any. means may be employed to provide a base o'r other device to support the storage tank or to provide means to suspend the tank without the necessity of a base.

I claim as my invention:

l. A hot Water storage tank particularly of the type which is electrically heated comprising a plurality of anniilar ring members each with inner and outer circumferential sections arranged one on each other to form a doublewalled container, each of said annular members forming by its inner circumferential section an annular part of the inner wall of the container and by its outer circumferential section an outer wall part of the container, and the inner and outer wall part of each annular member being interconnected by a substantially radial wall, the inner, outer and radial walls of each annular member forming an integral structure open on at least on axial side, the open side of each member being closed by the radial wall member of the next annular member axial direction, so that hollow annular spaces are formed between each two subsequent annular members, each annular ring member having a portion of a smaller annular configuration to telescopically interfit with an adjacent ring member in overlapping relationship, means to hold said annular ring members in the overlapping rel ionship, a top cover for the tank telescopically mounted on the top-most annular ring member and composed of inner and outer casings spaced from each other, a bottom cover composed of inner and outer casings and telescopically mounted on the bottom-most annular ring member, the top and bottom covers each having an outer member, and an outer sheath connected to the outer members to cover the annular ring members.

2 A hot water storage tank particularly of the type which is electrically heated comprising a plurality of annular ring members each with inner and outer circumfe'r'en tial sections arranged one on each other to form a double-walled container, each of said annular members forming by its inner circumferential section an annular part of the inner wall of the container and by its outer cijreuniferential section an outer wall part of the centainer, and the inner and outer wall part of each annular member being interconnected by a substantially radial wall, the inner, outer and radial walls of each annular member forming an integral structure open on at least one axial side, the open side of each member being closed by the radial wall member of the next annular member in axial direction, so that hollow annular spaces are formed between each two subsequent annular members,

each annular ring member having a portion of a smaller annular configuration to telescopically interfit with an ad: jacent ring member in overlapping relationship, means to hold said annular ring-members in the overlapping relationship, a top cover for the tank telescopically mounted on the top-most annular ring member and composed of inner and outer casings spaced from each other, a bottom cover composed of inner and outer casings and telescopically mounted I on the bottom-most annular ring member, the top and bottom covers each having an outer rim member, an outer sheath connected to the outer rim members to cover the annular ring member, and a plurality" of radial ribs spaced from each other and provided in the inner and outer casings in the top and bottom covers.

3. A hot Water storage tank particularly of the type which is electrically heated comprising a plurality of annular ring members each with inner and outer circumferntial sections arranged one on each other to form a double-walled container, each of said annular members fsrmingb its inner circumferential section an annular part of the inner wall of the container and by its outer circumferential section an outer wall part of the container, and the inner and outer wall part of each annular member being interconnected by a substantially radial wall, th inner, outer andradial walls of each annular member forming an integral structure open on at least one axial side, the open side of each member being closed by the radial wall member of the next annular member in axial direction, so that hollow annular spaces are formed between each two subsequent annular members, each annular ring member having a portion of a smaller annular configuration to telescopicallyinterfit with an adjacent ring member in overlapping relationship, a top cover for the tank telescopically mounted on the top-most annular ring member and composed of inner and outer casings spacedfrom each other, a bottom cover composed of inner and outer casings and telescopically mounted on the bottom-most annular ring member, the top and bottom covers each having an outer riininembe'r, an outer sheath connected to the outer rim members to cover the annular ring members, a plurality of radial ribs spaced from each other and provided in the inner and outer casings in the top and bottom "covers, and a plurality of stay members under tension in spaced relation passing through the annular nfng members to hold the latter in tight force contact with each other.

References Cited in the file of this patent UNITED STATES PATENTS 

